In the conventional direct mode communication technologies, primarily allocation of the communication resources is dominated by a base station, and the allocated communication resources are allocated by the base station to direct mode communication apparatuses that have a need for the communication resources. Then, the direct mode communication apparatuses can perform direct mode communications with other direct mode communication apparatuses via the communication resources allocated by the base station. However, such a resource allocation mechanism not only degrades the utilization efficiency of the spectrum resources, but also leads to an unduly high burden of the base station.
Specifically, in order to avoid interferences between direct mode communication apparatuses in a network due to repeated use of spectrum resources when the base station allocates communication resources to the direct mode communication apparatuses, the base station orthogonalizes the usable spectrum resources in such a way that the spectrum resource used by each direct mode communication connection is orthogonal to spectrum resources of other direct mode communication connections. In this way, interferences between the direct mode communication apparatuses can be avoided.
However, in situations where no interference is caused when direct mode communication apparatuses that are not adjacent to each other use a same spectrum resource to perform direct mode communications with other direct mode communication apparatuses respectively, such a mechanism that relies on the base station alone to allocate the communication resources will significantly degrade the utilization efficiency of the spectrum resources. On the other hand, relying on the base station alone to schedule all the communication resources will greatly increase the burden of the base station as the number of direct mode communication apparatuses in the network increases.
Accordingly, an urgent need exists in the art to provide a solution capable of improving the scheduling mechanism of the communication resources so as to significantly increase the utilization efficiency of the spectrum resources and ease the burden of the base station.